Third-rail insulator.



No. 808,222. PATENTED DEC. 26, 1905.

S. B. STEWART, JR. THIRD RAIL INSULATOR.

APPLIOATION FILED JULY 23.1903.

Witnesses;

Inventor: fi m Sqmuel fiStewortJr.

U NITED STATES PATENT OFFICE.-

SAMUEL B. STEWART, JR, OF SGHENEOTADY, NEiV YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

THIRD-RAH. lINSULATOR.

Specification of Letters Patent.

Patented Dec. 26, 1905.

Application filed July 23,1903- Se1ialN0.l66 6'79.

To all whom it may concern.-

Be it known that I, SAMUEL B. STEWAR'LJ r. a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements inThird-Rail Insulators, of which the following is a specification.

This invention relates to third-rail insulators, and has for its object the provision of such an insulator as can be cheaply manufactured and easily installed and which will be efficient and durable in operation.

Third-rail insulators as usually constructed comprise a shoe which is secured to the tracksleepers, an insulating-support mounted on said shoe, and a metal cap mounted on said support and adapted to support and secure the rail in position. The cap is usually provided with ears for thus securing the rail. In certain types of insulators wherein the cap is so related to the insulating-support that it can have no motion of rotation retaining-ears are placed at diagonally opposite points on the cap, and the rail is inserted in position between them by rotating the insulator with reference to the rail from the position which it is to permanently occupy, and after the rail has been inserted the cap is rotated back to its normal position.

It is a common construction in third-rail insulators to connect separate parts by means of plug-and-socket connections, and in the I types just described, in order to prevent relative rotation of parts so connected, the plugs and sockets are made angular in cross-section and the joints made still more tight by the use of cement, which is run in between the walls of the plug and the socket. Ithas been found, however, that trouble has been caused by breakage of the insulators, due to initial cracks at the vertices of the angles made in the manufacture and also from the cement becoming loose. It is therefore advisable that all surfaces be rounded rather than angular to avoid the initial cracking, and the vertical engaging surfaces between adjacent portions of theinsulator should be cylindrical and the parts loosely mounted, so that relative rotation between them may take place, thereby avoiding strains upon the insulator.

A construction having the characteristics above specified has been heretofore proposed; but in order that the rail may be securely fastened to the cap at all times the retaining-ears upon a cap of this construction must be directly opposite each otherthat is, approximately in a planeat right angles to the rail for if diagonally opposite movement of the cap with relation to the rail, which might easily take place when the vertical cooperating engaging surfaces of the insulator are cylindrical, might allow the disengagement of the rail from its support. This has been previously recognized; but difficulty has been experienced in producing a cap with ears located as described which could readily be applied to the rail and at the same time be convenient to handle and inexpensive to manufacture. Previous forms have required a special construction of rail or that the cap be slid on the lower flange from the end of each rail or else that the cap be manufactured with straight ears adapted to be bent over after the rail has been inserted between them. The special construction of the rail is inconvenient and expensive, the labor of installation is considerable when it is necessary to slide the cap on from the end of the rail, and where the straight ears are used it is necessarythat the cap or the ears be made of malleable material, and the labor and care required in the installation is considerable. It has been proposed to make one of the retaining-ears of the cap removable; but this form does not entirely fulfil the desired conditions, owing to the fact that the parts of the cap cannot be made duplicates of each other, thus making them expensive to manufacture and requiring care in mating the parts composing a cap. Moreover, the small size of the removable ear renders it liable to become lost.

In order to obtain all the advantages of free and loose cooperation of the parts, insure engagement between the rail and cap at all times, minimize the labor and care required in installation, and decrease the cost of manufacture, I propose to furnish an insulator having a shoe upon the sleeper, an insulating-support carried thereby, and a rail supporting and retaining cap mounted upon said insulating-support, the various parts of the insulator being loosely fitted together and their vertical engaging surfaces permitting relative rotation, thus obtaining the desired flexibility of the insulator. The retaining-ears upon the cap are manufactured in the final form, and in order that the caps may be readily assembled in position with relation to the rail they are formed of a plurality of portions upon which are carried the retaining-ears, and when assembled the ears engage the rail at directly opposite points, and the various portions of the cap and the ears thereon are held in supporting and retaining relation to the rail by engagement with their support. Moreover, the parts of which the cap, is formed may be duplicates, thus reducing the cost of manufacture and the care and labor required in installation.

The details of my invention will be best understood by reference to the following description, taken in connection with the accompanying drawings, of which Figure l is an elevation, partly in section, of my improved insulator with the rail in position; and Fig. 2 is a top plan view with the rail removed.

Referring to the drawings, A is a metal shoe having a socket into which the insulating-support B is fitted, said shoes being adapted to be secured to the sleepers or ties supporting the traffic-rails by bolts,screws, or other fastenings passing through holes, as /t, in the base of the shoe. In the bottom of the socket is a hole 9, the function of which will appear later.

Projecting into the socket of shoe A is a portion a of the insulating-support B, the upper portion of the support overhanging the edges of shoe A, so as to form a petticoat p, whereby the entry of moisture into the socket is prevented. Extending axially through the support B is a hole 0, which at its upper portion constitutes the cylindrical socket s and at its lower portion is narrowed into the channel c.

Resting upon the insulating-support B is the rail-supporting cap (J, composed of duplicate parts D and E, each comprising a plate (Z, a rail-retaining ear (2, and a semicylindrical plug portion 0'. Resting upon the cap and retained in place by ears 6 is the third rail R.

In assembling the insulator in connection with the "ail portions D and E are applied to opposite sides of the lower flange, so that the rail is embraced by the ears 0 at directly opposite points, the plug portions r then cooperating to form a substantially cylindrical plug, which is inserted in the socket s. The insulator may then be mounted in position. By means of this construction the rail R is held in secure relation to the cap, while at the same time the cap may have a motion of rotation with relation to support B. The support B may also have motion with relation to the shoe A.

During wet weather water may collect upon the surface of the cap, which, being divided, may not act to shelter the socket S, and therefore the water running down into the socket swould be retained, thereby causing corrosion of the metal portions, and in case of subsequent cold weather the freezing of the water might split the support B were it not pro vided with a channel a, through which such water is drained and finally discharged through the hole provided for that purpose in the base of the shoe A.

In accordance with the patent statutes 1 have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative and that the invention can be carried out by means other than the particular apparatus shown in the drawings.

hat I claim as new, and desire to secure by Letters Patent of the United States, is-

1. The combination of a rail, a supportingcap therefor composed of a plurality of parts, means upon said cap for securing said rail thereto, an insulating-support which loosely engages with the parts of the cap to hold them in position and maintain said securing means in retaining relation to the rail.

2. A rail-insulator comprising a cap composed of two integral parts each of which consists of a rail-retaining ear and a plug por tion, and an insulating-support having a socket for receiving said plug portions.

A rail-insulator comprising a cap composed of two duplicate integral parts each of which consists of a rail-retaining ear and a plug portion, and'an insulating-support having a socket for receiving said plug portions.

A. A rail-insulator comprising a cap composed of two duplicate integral parts each of 'which consists of a rail-retaining ear and a plug portion, and an insulating-support having a socket within which said plug portions are loosely seated.

5. The combination of a rail, a cap composed of a plurality of parts, a retaining-ear and a plug portion upon each of said parts, and an insulating-support for said cap having a socket to receive and loosely retain the plug formed by the cooperation of said plug portions.

6. The combination of a rail, a two-part cap for retaining and supporting said rail, an insulating-support for said cap, said cap having retaining-ears and portions engaging loosely with said support, whereby the ears are maintained in position to secure said rail.

7. A rail-insulator comprising a cap composed of duplicate parts arranged to engage with the rail and an insulating-support loosely engaging the parts of said cap to hold them in rail-engaging position.

8. A rail-insulator comprising a cap constructed in duplicate parts adapted to embrace the flange of the rail and an insulating-support for said cap constructed and arranged to loosely engage the parts of the cap in order to hold them in flange-embracing position.

9. The combination of a rail, and a divided supporting-cap therefor, rotatable in a horizontal plane and having a retaining-ear upon eachportion of said cap, the said ears being so placed as to engage the rail on opposite sides thereofltogether with a support therefor.

10. The combination of a rail, a divided supporting-cap therefor, each portion of said cap having a retaining-ear and aplugportion, and an insulating-support for said cap, having a socket in which the plug formed by the plug portions is rotatably mounted.

11. In a rail-insulator, a cap-support having asocket in its upper part unsheltered from the Weather, and a passage for draining said socket.

12. In a rail-insulator, a cap-support having a socket, a shoe in which said support is mounted, and registering passages in said support and said shoe, through which said socket is drained.

13. The combination of a rail, a divided supporting-cap therefor, having a plug portion and a retaining-ear mounted on each part, said ears being so placed as to engage said rail at points approximately opposite, and a support for said cap having a socket in which the plug formed by the plug portions upon the cap is rotatably mounted.

14. In a rail-insulator, a cap composed of duplicate integral parts, each part consisting of a rail-engaging ear and a plug portion.

15. As an article of manufacture, a cap portion for a rail-insulator consisting of a plate having a rail-engaging ear on its upper side, and a plug portion on its lower side, substantially as described.

16. The combination of a rail, a supporting and retaining cap therefor, said cap having rail-engaging ears and being divided along a line between said ears, each portion of said cap having one of said ears and a semicylindrical plug portion, and a support for said cap having a cylindrical socket into which the plug formed by said plug portions is inserted and within which the plug is free to rotate.

17. A rail-insulator comprising a cap constructed in duplicate parts with diametrically opposite ears cast in final shape for retaining the rail, and a suitable support constructed and arranged to hold the parts of the cap in position to retain the rail, the parts of the cap being loosely supported so that they may freely rotate.

18. In combination, a rail, a sectional cap having rail-retaining ears, and a support, said cap and support having cooperative male and female members whereby the sectional cap is revolubly held in rail-retaining position.

19. In a rail-insulator, an insulating-support and a sectional cap having rail-retaining cars, said support and cap having cooperating members arranged to hold the sectional cap revolubly in rail-retaining position.

In witness whereof I have hereunto set my hand this 21st day of July, 1903.

SAMUEL B. STEIVART, JR.

Witnesses:

BENJAMIN B. HULL, HELEN ORFORD. 

